On Tue, 17 Mar 2020 at 07:42, AKASHI Takahiro <takahiro.aka...@linaro.org> wrote:
> Summary > ======= > 'UpdateCapsule' is one of runtime services defined in UEFI specification > and its aim is to allow a caller to pass information to the firmware. > This is mostly used to update firmware binary on devices by instructions > from OS. > > In this patch series, all the related definitions and structures are given > as UEFI specification describes and basic framework for capsule support is > implemented. Currently supported types of capsule are > * firmware update (Firmware Management Protocol or simply FMP) > * variable update > > UpdateCapsule is a runtime services function, but is, at least initially, > provided only before exiting boot services alike other runtime functions. > This is because modifying storage which may be shared with OS must be > carefully designed and there is no general assumption to do that as in > the case of [Get/]SetVariable. > Instead, any capsule can be handed over to the firmware as a file on > a specific file system. In other words, we only support "capsules on disk" > for now. > > Regarding firmware update, most of functionality is provided by FMP > driver and it will be by nature system/platform-specific. So you can and > should implement FMP drivers based on your system requirements. > In this patch series, only a simple FMP driver based on FIT image for > a single region is supported. (So it is "for reference only") > See more details in "efi_loader: capsule: add simple firmware management > protocol." > > Regarding variable update, the implementation here is based on a draft > proposal[1] by Peter in Boot-arch ML. The specification should be discussed > and finalized first. So the code doesn't fully implement Peter's idea. > > [1] > https://lists.linaro.org/pipermail/boot-architecture/2018-October/000883.html > > Patch structure > =============== > Patch#1-#4: preparatory patches > Patch#5-#11: main part of implementation > Patch#12-#14: utilities and tests > > With the changes that I suggested in a couple of patches, I am able to test the capsule-on-disk update of the u-boot firmware image on the qemu arm64 platform. I have also tested the capsule update functionality via the 'efidebug capsule update -v <capsule address>' command. Thanks! -sughosh
